Anyone knows how `hashCode()` is implemented by th...

# announcements

[louiscad]

Anyone knows how hashCode() is implemented by the Kotlin compiler in a data class having a `fun`ction property constructor parameter? e.g.: data class Option(val id: Int, val desc: () -> String)

[mg6maciej]

It calls the function 🧌

[louiscad]

Not possible, this would be huge flaw as this is not documented, and this could have side-effects 😛

[mg6maciej]

To be honest I don't know, but I'd guess it is the default hashCode, i.e. takes address of the function object.

[kirillrakhman]

@louiscad why would it be a flaw? What's the difference to data class Foo(val id: Int, val desc: Description) where Description doesn't implement hashCode()?

[mg6maciej]

That was a joke on my side. desc.invoke().hashCode()

[louiscad]

@kirillrakhman I said why it'd be a flaw to invoke the property function in hashCode() (and equals(other: Any)). Any already implements hashCode(), but it can be less efficient if you stick to the default implementation

[kirillrakhman]

Ok I understand. Of course, it doesn't invoke the function.